Process for the antistatic treatment of light-sensitive silver halide photographic materials with phosphine oxide

ABSTRACT

A PHOSPHINE OXIDE HAVING THE GENERAL FORMULA   O=P(-R1)(-R2)-R3 OR O=P(-R1)(-R2)-X-P(=O)(-R1)-R2   WHEREIN R1, R2 AND R3 ARE INDIVIDUALLY AN ALKYL, ARYL OR ARALKYL GROUP AND X IS AN ALKYLENE GROUP, IS INCORPORATED INTO A LIGHT SENSITIVE SILVER HALIDE PHOTOGRAPHIC MATERIAL TO IMPART THERETO AN ANTISTATIC EFFECT.

United States Patent (3 No Drawing. Filed July 2, 1968, Ser. No. 741,883Claims priority, application Japan, July 7, 1967, 42/43,325 Int. Cl.G03c 1/78 U.S. Cl. 96-87A 2 Claims ABSTRACT OF THE DISCLOSURE Aphosphine oxide having the general formula wherein R R and R areindividually an alkyl, aryl or aralkyl group and X is an alkylene group,is incorporated into a light sensitive silver halide photographicmaterial to impart thereto an antistatic effect.

This invention relates to a process for the antistatic treatment oflight-sensitive silver halide photographic materials, characterized byusing phosphine oxides.

When a light-sensitive silver halide photographic material has beendeveloped, there are some cases where spots in the form of branches orfluifs are found therein. These spots are so-called static marks, andare said to be derived from such phenomenon that the surface of thelight-sensitive material has been electrostatically charged due tomechanical abrasion and the electrostatic charge has been discharged toexcite the light-sensitive material. Such undesirable static chargeresults not only in the formation of static marks but also in theadhesion of dust onto the surface of light-sensitive material. Suchdrawbacks due to static charge unavoidably takes place in substantiallyall the steps of production and handling of lightsensitive materialswhere the materials undergo abrasion. For example, said drawbacks arebrought about in such production steps as the step for coating ofemulsion, the steps of cutting and packaging light-sensitive materials,and the like steps; in the case of taking sheet films from a box; in thecase of taking pictures, particularly in filming; or in the case ofhandling of light-sensitive materials before development. Such drawbacksdue to static charge are sometimes brought about also in the case ofreleasing of light-sensitive materials, in addition to the case ofabrasion. That is, after emulsion-coating and drying, a light-sensitivematerial is rolled up, in general, and is then successively unrolled inorder to transfer the material to subsequent step, or a rolled printingpaper is successively released to be subjected to printing. In thiscase, static charge due to frictional electricity is generated betweenthe surface and the back side of the light-sensitive material at themoment when it is released from the rolled portion. Further, when aprinting paper is subjected to ferrotype drying and is then taken out,static charge due to frictional electricity is generated as Well betweenthe metal surface and the surface of light- 'ice sensitive material tocause such a phenomenon that the superposing of the printing papercannot be effected immediately.

As a procedure for preventing such drawbacks due to static charge, ahygroscopic material is frequently incorporated into the constitutiveelements of a light-sensitive material. This procedure, however, iseffective only in the case where humidity is relatively high, and isineffective at a dry time when static charge is frequently discharged.Further, in case humidity is excessively high, said procedureaccompanies such drawback as the mutual adhesion of film surfaces oflight-sensitive material. In addition to said hygroscopic material,there are a considerable number of compounds which have been known asantistatic agents. However, in application of antistatic agents tolight-sensitive photographic materials, it is a required condition thatthey should not have any detrimental efiect on photographiccharacteristics of the lightsensitive materials, such as speed,gradation, fog, stability, and the like. It is therefore extremelydifficult to find excellent antistatic agents applicable tolight-sensitive silver halide photographic materials.

As the result of various studies on excellent antistatic agents havingno detrimental effect on light-sensitive silver halide photographicmaterials, the present inventors have found that compounds representedby the general formula wherein R R and R individually represent analkyl, aryl or aralkyl group; and X represents an alkylene group, areexcellent antistatic agents.

When the above-mentioned compounds are incorporated into at least onelayer of silver halide emulsion layer, subbing layer, inter layer,filter layer, anti-halation layer, protective layer and backing layer,it is possible to obtain light-sensitive silver halide photographicmaterials which are markedly less in drawbacks due to static charge.Further, the incorporation of the aforesaid compounds gives nodetrimental elfect to the characteristics of light-sensitivephotographic material, such as speed, gradation, fog, and the like.

If the above-mentioned compounds are increased in hydrophobic propertiesby extending the chain lengths of, for example, alkyl groups of R R andR in the aforesaid general formulas, the compounds are deteriorated inwater solubility, with the result that the incorporation thereof intothe constitutive elements of light-sensitive materials becomesdifiicult. This difficulty, however, can be overcome by the combinationuse of an excellent anionic surface active agent. This combination useis not only effective for the solubilization of the present compoundsbut also gives the following advantages:

That is, the use of anionic surface active agents makes favorable thespreadability of photographic emulsions, in general, butdisadvantageously increases the drawbacks due to static charge.Accordingly, it is impossible to select the kind of said agents onlyfrom the standpoint of spreadability. However, when said agents are usedin combination with the present compounds, the question of drawbacks dueto static charge is solved, with the result that in the selection ofanionic surface active agents, it becomes possible to give priority tothe spreadability thereof.

Examples of phosphine oxides having the aforesaid general formulas areas follows:

be incorporated into said layers vary depending on the kinds ofcompounds and of layers, but are preferably The phosphine oxidesrepresented by the above-mentioned general formulas are synthesized, ingeneral, either by reacting phosphorus hemitetraiodide with an alkyliodide and then treating the reactor mixture with concentrated nitricacid, or by reacting phosphorus oxychloride, or a substituted phosphorusoxychloride in which the chlorine has been substituted by othersubstituent, with a Grignard reagent. The process for the synthesisthereof is disclosed in such literature as E. S. Levchenko, Y. V. Piren,A. B. Kilsanov: Zhurnal Obshchei Khimii, 1976-81 (1960), or G. M.Kosolapoff, R. F. Struck: Journal of the Chemical Society, 1959, 3950-2.

In incorporating the compounds having the aforesaid general formulasinto the silver halide emulsion layer, subbing layer, inter layer,filter layer, antihalation layer, protective layer and backing layer,the compounds may be used in the form of solutions in suitable solventssuch as water or alcohols. Alternatively, said solutions may be sprayedonto the surface of light-sensitive photographic materials, orlight-sensitive materials may be immersed in said solutions. In the caseof compounds poor in water solubility, they may be incorporated afterdissolving in solutions of suitable surface active agents less ininfluence on photographic emulsions, such as for example, anionicsurface active agents, as mentioned before. Alternatively, they may beincorporated, into emulsions, in the form of dispersions formed bydissolving the compounds in suitable solvents such as dibutyl phthalateand the like, forming the solutions into colloidal solutions by means ofa colloid mill or of ultrasonic waves, and dispersing the colloidalsolutions into water. Further, the compounds of the present inventiongive favorable results even when incorporated into such treatingsolutions as developer, stopper, fixing solution and thickener,particularly into the thickener. The amounts of the present compounds towithin the range of from about 0.1 mg. to about 1 g. per square meter oflight-sensitive materials.

The following examples illustrate the present invention.

EXAMPLE 1 The compound V was dissolved in water containing sodiumdodecylbenzenesulfonate to form a 1% solution. The solution was sprayedonto the surface of a high speed X-ray film, and was then dried. On theother hand, the same X-ray films were immersed for 1 minute individuallyin the above-mentioned solution, and in a 1% sodi umdodecylbenzenesulfonate solution, and were then dried. These 3 treatedfilms and an untreated X-ray film were allowed to stand for 24 hoursunder the conditions of a relative humidity of 30% and a temperature of25 C. Therefore, the surfaces of said films were abraded with nylon andpolyester cloths, and then the films were developed, without exposure,according to an ordinary procedure using a developing solution for X-rayfilms. In the film treated with the solution containing no compound Vand in the untreated film, the generation of considerably marked staticmarks was observed, whereas in the films treated with the solutioncontaining the compound V, no generation of static marks was observed.

On the other hand, the films treated with the solution containing thecompound V were subjected to sensitometry according to JIS procedure,but no influence on the films in speed, gradation and fog due totreatment with the solution containing the compound V was observed atall. Further, these films were stored for 3 days both in a thermostat at55 C., and under the conditions of a temperature of 50 C. and a relativehumidity of and were then subjected as well to sensitometry according toH8 procedure. In this case also, it was found that the compound V gaveno influence to the films.

EXAMPLE 2 The compound XIX was dissolved in a 4% solution of sodiumdecyl-isoamyl sulfosuccinate so that the concentration thereof became2%. This solution 'was poured into a 2% gelatine solution, which was tobe employed as a protective layer, in an amount of 20 cc. per liter ofsaid gelatine solution. The mixed solution was applied as a protectivelayer onto the surface of a high speed X-ray film and was then dried.The resulting lightsensitive material was subjected to entirely the sametest as in Example 1 together with the said X-ray film having theprotective layer Which had not been incorporated with the compound XIX,whereby the same results as in Example 1 were obtained.

EXAMPLE 3 10 cc. of a 5% methanol solution of the compound VIII wasadded to 1 l. of a green-sensitive silver iodobromide color-photographicemulsion. To the mixture was added a solution prepared by dissolving ina 1 N caustic soda solution 20 g. of the magenta coupler, 1-(4-phenoxy-3'-sulfophenyl)-3 heptadecyl pyrazolone, and then adjusting theresulting solution to pH 6.8 by means of citric acid. The thus obtainedemulsion was applied onto a cellulose triacetate base and was thendried. The resulting film was subjected to entirely the same test as inExample 1 together with a sample film to which the compound VII=I hadnot been added. Provided that, in the above case, the films weredeveloped according to an ordinary procedure by use of a color developercomposed mainly of diethyl-p-phenylenediamine, and were then subjectedto the after-treatment. As the result, the generation of static markswas completely inhibited by incorporation of the compound VIII, but saidcompound gave no influence to photographic characteristics of the film,i.e. speed, gradation and fog. Further, in the heat resistance test ofthe film also, the compound VIII gave no detrimental effect.

EXAMPLE 4 2 cc. of a 2% aqueous solution of the compound VI was added toa 5% aqueous gelatine solution containing an antihalation dye. To themixed solution, 3 cc. of a 5% saponin solution was further added, andthe mixture was applied onto the surface of a triacetate base and wasthen dried. Onto the reverse side of the base, a high speed photographicnegative emulsion was applied, and as the protective layer thereon wasapplied a layer, into which 300 mg. per liter of the gelatine solutionof the above-mentioned compound had been incorporated in the same manneras in Example 2. The resulting lightwherein R R and R individuallyrepresent an alkyl, aryl or aralkyl group and X is an alkylene group.

2. A developer containing the phosphine oxide of claim 1.

References Cited UNITED STATES PATENTS 2,420,610 12/ 1945 Meeller 9687A2,968,554 1/1961 Land 9666 3,385,704 5/1968 Grabhofer et a1. 96-663,377,292 4/1969 Halvorson 252-3013 3,422,079 1/ 1969 Welch et al 260-NORMAN G. TORCHIN, Primary Examiner I L. GOODROW, Assistant Examiner US.Cl. X.R. 9666

